A generalization of plexes of Latin squares
نویسنده
چکیده
A k-plex of a latin square is a collection of cells representing each row, column, and symbol precisely k times. The classic case of k = 1 is more commonly known as a transversal. We introduce the concept of a k-weight, an integral weight function on the cells of a latin square whose row, column, and symbol sums are all k. We then show that several non-existence results about k-plexes can been seen as more general facts about k-weights and that the weight-analogues of several well-known existence conjectures for plexes actually hold for k-weights.
منابع مشابه
Indivisible partitions of latin squares
In a latin square of order n, a k-plex is a selection of kn entries in which each row, column and symbol occurs k times. A 1-plex is also called a transversal. An indivisible k-plex is one that contains no c-plex for 0ocok. For orders n= 2f2,6g, existence of latin squares with a partition into 1-plexes was famously shown in 1960 by Bose, Shrikhande and Parker. A main result of this paper is tha...
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 311 شماره
صفحات -
تاریخ انتشار 2011